You are mixing up the csh-builtin with /usr/bin/nice. From csh(1):
nice
nice +number
nice command
nice +number command
The first form sets the scheduling priority for this shell
to 4. The second form sets the priority to the given
number. The final two forms run command at priority 4 and
number respectively. The greater the number, the less CPU
the process will get. The super-user may specify negative
priority by using `nice -number ...'. Command is always
executed in a sub-shell, and the restrictions placed on
commands in simple if statements apply.
--
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Michael van Elst
Internet: mlelstv%serpens.de@localhost
"A potential Snark may lurk in every tree."
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